oracle rank() over()

oder by 字段

字段数据重复 rn 重复

　　

select b.*,case when rn=1 then '保留'

row_number() over(partition by order by 字段)

字段重复 rn 不重复

　　

else '删除' end from (select RANK() over(partition by zqdm, zqjc, sj, xynx, jyfs, zxjz, zxsyl, ljcjl, dzf, jqpjjj, jppjsyl, pmll, zqpj, ztpj, cjrq order by oper_user) rn, a.* from dcs_reserved_data_20210611 a ) b where b.cjrq> date'2021-01-26'